Mercedes Benz E300D Automatic 1994 Model
 

During idling specially at traffic signals when the vehicle is kept idling, the Engine noise is embarassingly high inspite of adjusting the idle speed. Can someone suggest any remedy. It has run 58900miles or 94240 kms. Alternatively, I am also thinkng of replacing the Engine with some used CRDI Engine that fits into this vehicle. If so, from where can I locate or get one from some dealer. Which year of manufacture of the CRDI engine do you recommend. Thanks for your time and assistance. Regards Nagaraj